Titre : Hysteretic spin crossover complexes and macrocyclic single-molecule magnets.
La conférence sera prononcée par la professeure Sally Brooker du Département de chimie de l'University of Otago (Nouvelle-Zélande). Elle sera donnée en anglais.
Résumé : Our interests in spin crossover (SCO) started when we identified that a dicobalt complex of a [2+2] Schiff-base macrocycle based on 3,6-diformylpyridazine, L, [CoII2L(NCS)2(SCN)2], had unique SCO behaviour. Our focus in the area of SCO then moved on to the formation of related triazole-based complexes of iron(II). The first iron complex we prepared, [FeII2(PMAT)2](BF4)4•DMF, utilised a bis-terdentate triazole ligand, PMAT, and led to the first structural characterization of a mixed spin state dimetallic complex. More recently we have also started exploring the controlled preparation of Single-Molecule Magnets (SMMs). Inspired by the [3+3] macrocycles described by Nabeshima and MacLachlan, we have prepared M3Ln SMMs using Schiff-base macrocycles such as (LPr)6- with approximate 3-fold symmetry. This lecture will describe our recent results in the SCO and SMM fields. It will focus on self-assembling systems featuring transition metal complexes of (a) related triazole-based ligands, (b) new pyrazine-based ligands for SCO and (c) a new class of macrocyclic 3d-4f SMMs.
